Lathe tool grinding fixture



May 4, 1943. w. R. LANDY LATHE TOOL GRINDINGFIXTURE Filed Aug. 27, 1941 4 and} Willi a??? Patented May 4, 1943 V 2,317,99ii

UNITED STATES PATENT OFF-ICE 2,317,996 i l LATHE TOOL cumulus; FIXTURE 1 f William It. Landy, Minneapolis, Minn. I v 7 Application August 27, 1941, 'Serial No. 498,461

6 Claims.

My present invention provides a simple and highly efficient device for holding a cutting tool such as used in lathes, planers, shapers, and the like, and to accurately position the same with respect to the grinding wheel and the various angles on which the cutting end of the tool should be ground.

Generally stated, the invention consists of the novel devices, combinations of devices, and arrangement of parts hereinafter described and defined in the claims.

The main element of the fixture or device is in the nature of a metallic block provided with means for securely clamping the cutting tool thereon, and formed with various beveled surfaces which, when pressed on a flat supporting table or the like, determines the various angles on which the tool should be ground.

A commercial form of the device in a preferred embodiment is illustrated in the accompanying drawing wherein like characters indicate like parts throughout the several views.

Referring to the drawing:

Fig. 1 is a view in perspective showing the fixture or grinding device withthe cutting tool removed therefrom;

Fig. 2 is a section taken on the line 2-2 of Fig. 1 but showing the cutting tool clamped in position on the block;

Fig. 3 is a front elevation of the fixture shown in Fig. 1 with the cutting tool clamped therein as shown in Fig. 2;

Fig. 4 is a side elevation of the device with the cutting tool applied to the block, as shown in Figs. 2 and 3, and indicating also by dotted lines a grinding wheel;

Fig. 5 is a view corresponding to Fig. 3 but illustrating a different adjustment of the fixture;

Fig. 6 is a side elevation of the device in another position for grinding;

Fig. 7 is a plan view of the device shown in Fig. 6 with some parts broken away; and

Fig. 8 is a plan view of the eccentric element of the clamping device removed from working position and turned upside down in respect to the other views.

In Figs. 3, 4, 5- and 6 a grinding wheel y is indicated by dotted lines. The metallic block or body of the fixture is indicated as an entirety by the numeral l0; and the lathe tool isindicated by the numeral II. This block Ill is preferably formed with a flat top surface that is cut through by a longitudinal groove l2. At one side the groove l2 has an offset pocket He. The numeral l3 indicates a threaded stud, the lower end of which is anchored in the block and projects up ward through the pocket l2a. Loosely mounted on the stud I3 is a clamping eccentric l4 shown as formed with a projecting knurled rim Ha. Working with threaded engagement on the threaded end of the stud I3 is a clamping nut The cutting tool I I, when placed in the groove l2, as best shown in Fig. 2, will be tightly clamped against one side of said groove by rotation of the eccentric I l; and when the nut I5 is then tightened, the flange I la. will press the tool II tightly downward against the bottom of said groove. In this way cutting tools of varying cross-section, within certain limits, may be tightly clamped in the block.

In Figs. 3, 4, 5 and 6 a horizontal supporting table [6 is shown as located adjacent to the grinding wheel :1 In describing the angles of the surfaces of the block ill, the top of the said block is treated as a horizontal plane. The bottom of the block is formed with bearing surfaces I00. and llld which, from the medial longitudinal line of the block, converge slightly in respect to thehorizontal or fiat top of the block, the said angles of divergence being decidedly acute and, as shown, being approximately 10. At its sides the block I0 is formed with bearing surfaces lllb and [lie that are acute angles to perpendiculars projected from the fiat top of the block, the said angles, as shown in this particular instance, being approximately 14 with respect to said perpendiculars. In longitudinal sections the beveled surfaces Illa, Hid, lb and lile are parallel tothe medial axis of the block.

For a further important purpose the rear or tail portion of the block In, at its under surface. is provided with a flat beveled surface lllc. This surface lilo in cross-section is parallel to the upper surface of fiat bearing surface Hlc is approximately 15 to the top of the block. However, the said angles above definitely given are not limiting and may be varied according to the bevel which is desired to be given to the surface of the cutting tool.

The fixture or grinding device described may be very advantageously used as follows: First, place the device, as shown in Figs. 3 and 4, with its fiat bottom surface Illa on the supporting table and move the two against the side of the grinding wheel, thereby producing on the end of the tool II the beveled clearance surface Ila.

Next, turn the block with its beveled fiat edge lob on the supporting table and move the tool against the side of the grind stone, as shown in the block. Also, as shown, the

the upper surface of tool H the inclined A cutting tool ground as just described would be adapted to cut by a movement from left to right or downward in respect to Fig. 7, and a tool thus ground would be called a right-hand cuttin tool. The operation for grinding a tool for cutting in the opposite direction, to wit: by'movement from right toward the left would be performed by an operation such as above described, except that instead of placing the block on its surface10a=it would b'e-placed on'-l'ts-surface Ind in tlfe firstinstance, and in the: second instance, would be placed on its beveled side or edge surface I lie instead of being placed on its surface lflb as-previously described;

A preferred form of the device has been described,.but it will be-understood that alterations in thedetai1sof construction and arrangement of the parts-may be made within the spirit of the invention herein disclosed and claimed: As is evident,. if the devicewere to be used only for grinding; cutting tools forright-hand cutting, the surfaces Nd and Ille'could be omitted, or conversely, for grinding onlytoolsifor left-hand cutting, the surfaces Hla and lllb could be omitted.

In: the above described device the fixture or device: for holding a; cutting tool for grinding is the' bottom of thegroove I! that constitutes the longitudinally extended tool-holdingsurface and this surface l2'is in the plane parallel to'the top of the block.

l. A- grinding fixture of the kind described in theform of a block provided'witlralongitudinal- 13 extended tool-holding surface, said block-.7 having. at. bottomsupporting surface which; in transverse section,. is at an acute angle to said toole holding? surface, and in longitudinal section, is

7 to said bottom bearing surface.

3. A grinding fixture of the kind described in the form of a-block provided with a longitudinally extended tool-holding surface, said block having bottom supporting surfaces which, in transverse section, are at the same acute angle to said tool-holding surface and, in longitudinal section, are parallel to said tool-holding surface; said block, at its rear, having a tail end supporting surface which, in longitudinal section, is at an acute angle to said tool-holding surface and, in

transverse section, is'parallel to'the planeof said tool-holding surface, said block having means for clamping the cutting tool against said toolholding surface.

4. The structure defined in claim 3 in which said block, at its sides, has bearing surfaces that, in longitudinal section, are parallel tosaid toolholding surface and, in transverse section, are at a common oblique angle to said bottom bearing surfaces.

5. The structure defined in claim 1- in which said tool-holding surface is formed by a groove extended longitudinally of the top of said fixture, and in further combination with means applied to the top of said fixture for clamping a tool in said groove.

6. The structure defined in claim 3 in which said tool-holdin surface is formed by a groove extended longitudinally of the'top of said fixture, and in further combination with means applied tothe top ofsaid' fixture for'clamping a tool in said groove.

. WILLIAM- R. LANDY. 

